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 ###Instrução: Quando a altitude crítica é o nível do mar, qual é a razão de compressão para uma relação de engrenagem do supercharger de 7:1?
 ###Tabelas: CREATE TABLE churches_belonging_to_the_assembly_of_canonical_bishops_of_north__&__central_america (churches_belonging_to_the_assembly_of_canonical_bishops_of_north__&__central_america_id AUTO_INCREMENT PRIMARY KEY, Adherents INT, Regular Attendees INT, % of adherents VARCHAR, Monasteries INT, Parishes INT, Average Parish Size INT) CREATE TABLE specifications_r-985_wasp_junior_sb (specifications_r-985_wasp_junior_sb_id AUTO_INCREMENT PRIMARY KEY, Engine VARCHAR, Power, continuous VARCHAR, Critical altitude This is the highest altitude at which the engine can achieve its full continuous power rating. Above this altitude, power falls off with height as with a naturally aspirated engine . See Supercharger#Altitude effects for details. VARCHAR, Power, takeoff VARCHAR, Compression ratio VARCHAR, Supercharger gear ratio VARCHAR, Octane rating VARCHAR, Dry weight VARCHAR) CREATE TABLE first_class_bowling_statistics (first_class_bowling_statistics_id AUTO_INCREMENT PRIMARY KEY, Player VARCHAR, Matches INT, Overs VARCHAR, Maidens INT, Runs INT, Wickets INT, Average VARCHAR, Economy VARCHAR, 5w INT, 10w INT, Best Bowling VARCHAR) CREATE TABLE territorial_and_overseas_regions_recordholders (territorial_and_overseas_regions_recordholders_id AUTO_INCREMENT PRIMARY KEY, Country VARCHAR, Territory VARCHAR, Name VARCHAR, Birth date VARCHAR, Death date VARCHAR) CREATE TABLE patrol (patrol_id AUTO_INCREMENT PRIMARY KEY, Class VARCHAR, Ships in class VARCHAR, Pennant Number INT, Unit VARCHAR, Builder VARCHAR, Commissioned VARCHAR)  
SELECT Compression ratio FROM specifications_r-985_wasp_junior_sb WHERE Critical altitude This is the highest altitude at which the engine can achieve its full continuous power rating. Above this altitude, power falls off with height as with a naturally aspirated engine . See Supercharger#Altitude effects for details. = sea level AND Supercharger gear ratio = 7:1